Cocaine-associated chest pain

Background

Cocaine is a catalyst for CAD & up to 6% of cocaine related CP develop an MI, however, a 9-12 hour period of ECG's and serial troponins can be safe. Of the 334 pts studied, if both were negative, no deaths from CV events occurred at 30 days. 4 pts did have non-fatal MI's but were using coc at the time.

Epidemiology

• Causes vasculitis
• 6% incidence of AMI w/ cocaine CP
• Cocaine assoc c 24x risk of true MI

Clinical Features

• Chest pain in the setting of cocaine or related stimulant use
• Cocaine metabolites can persist for up to 24hrs and cause delayed or recurrent coronary vasoconstriction

Differential Diagnosis

Chest Pain (DDx)

Diagnosis

• 1-3hrs onset from last use
  • If >3 hrs = lower risk of MI
• Most with characteristic pain
• Dyspnea, diaploresis, and nausea
• Most have nl vitals

Management

• ASA, NTG, O2
• Benzos directed at symptom relief, not necessarily HTN and tachycardia
• Consider NTG, Nitroprusside, Phentolamine, or CCB (in benzo non responders)
• Avoid beta blockers due to the possibility of unopposed alpha activity. Labetolol although offering the theoretical advantage of blocking both alpha and beta receptors does not reverse coronary artery vasoconstriction
  • Though not accepted in common practice, new evidence suggest a benefit to using beta blockade in these patients
• Consider NaHOC3 for Ventricular Arrythmias immediately following cocaine use
  • Reverses cocaine induced QRS prolongation by Na channel blockade

Disposition

• May discharge after: 9-12 hour period of ECG's and serial troponins, if both are negative
  • In NEJM 2/03; n=334; outcome of zero events at 30dys if no more cocaine

Risk Stratification

• Lower:
  • Also low risk if ecg normal and without ischemic changes
  • Cocaine can however cause AMI, dilated cardiomyopathy, CHF

See Also

• Cocaine
• Cocaine intoxication
• Cocaine Withdrawal
• Acute Coronary Syndrome (Main)